1. Field of the Invention
The invention relates to artificial orthopaedic implant prosthesis, and particularly, but not exclusively, to dental implants.
2. Description of the Prior Art
Presently, dental implants to replicate the function of an extracted or lost tooth, do so by rigidly fixing a primarily metallic implant to a bone-implant site. Although these implants have provided the dental industry with a certain degree of success, the absence of the biomechanical periodontal ligament, which evenly distributes the occlusal loads to the entire implant site, has caused the bone to resorb over time in certain regions of the implant.
Over the last twenty-five years many root formed dental implants have been designed to replace natural dentition and provide for both aesthetic and functional occlusion. Although these designs provided for certain distinct mechanical characteristics for attaching the adjoining bone to the implant, they do not address the replacement and functional significance of the extracted periodontal ligament. Since the periodontal ligament acts as an intermediate barrier between the natural dentition and the osteodontic site (which absorbs and uniformly distributes the occlusal loads), the omission of such a feature can be devastating to an implant's success. Presently, many groove, thread, and hole implant designs are available to mechanically fixture and permanently lock the implant to the bone without any consideration for the structural loading to the implant site and the significance of the periodontal ligament.
In 1983, an attempt was made to provide an implant system that simulated the physiological function of the periodontal ligament by inserting an intermediate attachment between the coronal element and the artificial root made from an elastic polymer. Although, in principle the design provided for a method to absorb the normal occlusion, the design failed to uniformly distribute the stress to the underlying bone that the implant was attached to. Furthermore, due to the weak mechanical characteristics of the elastic material, failure of this intermediate component was inevitable.
Since then, many attempts have been made using computer aided finite element analysis to evaluate the stress distribution of various implant geometries in order to find the ideal design, assuming rigid fixation to the attached bone. Although this data has provided significant insight to the structural behavior of many geometries that exist today, few new practical designs using this technology have been developed due to their manufacturing and surgical requirements.
What is needed is a specific thread geometry to evenly distribute the occlusal loads throughout the entire length of the implant.
The object of my invention is to emulate, with a dental implant, the anatomical conditions of natural dentition using a defined geometry and unique material, that can be easily manufactured and surgically placed.
Another object of my invention is to provide the implant with an interlocking mechanism to drive and secure the implant into the jaw and act as a receptor for securing a prosthetic attachment.
It is further the object of my invention to uniformly distribute the stress throughout the entire length of the implant, and prevent bone loss, buy using a specially designed mechanically locking tapered thread.
These and other objects of my invention will be apparent from the following description taken with reference to the accompanying drawings.